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81.
Human interleukin-4 (huIL-4) has been shown to inhibit the growth in vitro of cells from patients with acute lymphoblastic leukemia (ALL). With the aim of determining whether this cytokine might be useful in the treatment of patients with ALL, the effects of huIL-4 on human B- cell precursor ALL engrafted in severe combined immunodeficient (SCID) mice were examined. The inhibition of [3H] thymidine uptake of primary ALL cells by huIL-4 was maintained following engraftment and passage of leukemia in SCID mice. Five of seven xenograft leukemias showed significant inhibition in vitro by huIL-4 at concentrations as low as 0.5 ng/mL; furthermore, huIL-4 counteracted the proliferative effects of IL-7. When used to treat two human leukemias engrafted in SCID mice, huIL-4 200 microgram/kg/d, as a continuous 14-day subcutaneous infusion, suppressed the appearance of circulating lymphoblasts and extended survival of mice by 39% and 108%, respectively, the first demonstration of IL-4 activity against human leukemia in vivo. The mean steady-state huIL-4 level in mouse plasma during the infusion was 1.46 ng/mL (SEM +/- 0.14 ng/mL), which was similar to concentrations found to be effective in vitro. ALL cells obtained from mice relapsing after huIL-4 treatment continued to show inhibition by the cytokine in vitro. These data suggest that IL-4 may be useful in the treatment of patients with ALL.  相似文献   
82.
Interleukin-6 (IL-6), a product of bone marrow stromal cells (BMSCs), is a growth factor for multiple myeloma (MM) cells. Transforming growth factor-beta1 (TGF-beta1) is also produced by BMSCs and can regulate IL- 6 secretion by several tissues, including BMSCs. The present study was designed to characterize in vitro tumor growth regulation by TGF-beta1 in MM. Sorted CD38+CD45RA- MM cells secreted significantly more TGF- beta1 (8.2 +/- 2.0 ng/mL) than peripheral blood mononuclear cells (P < .001), splenic B cells (P < .001), and CD40 ligand (CD40L) pretreated B cells (P < .05). TGF-beta1 secretion by MM-BMMCs (3.8 +/- 0.9 ng/mL) was significantly greater than by N-BMMCs (1.2 +/- 0.1 ng/mL, P < .001). MM-BMSCs also secreted significantly more TGF-beta1 (6.6 +/- 2.5 ng/mL, n = 11) than N-BMSCs (4.4 +/- 0.6 ng/mL, P < .02, n = 10) and N- BMSC lines (3.9 +/- 0.2 ng/mL, P < .02, n = 6). TGF-beta1 secretion was correlated with IL-6 secretion in MM-BMSCs. Anti-TGF-beta1 monoclonal antibody both blocked IL-6 secretion by BMSCs and inhibited the increments in IL-6 secretion by BMSCs induced by MM cell adhesion. Moreover, exogenous TGF-beta1 upregulated IL-6 secretion by MM-BMSCs, normal BMSCs, and CD38+ CD45RA- MM cells, as well as tumor cell proliferation. This is in contrast to the inhibitory effect of TGF- beta1 on proliferation and Ig secretion of normal splenic B cells. Finally, retinoblastoma proteins (pRB) are constitutively phosphorylated in MM cells; TGF-beta1 either did not alter or increased pRB phosphorylation. pRB are dephosphorylated in splenic B cells and phosphorylated in CD40L triggered B cells in contrast to its effects on MM cells, TGF-beta1 decreased phosphorylation of pRB in CD40L treated B cells. These results suggest that TGF-beta1 is produced in MM by both tumor cells and BMSCs, with related tumore cell growth. Moreover, MM cell growth may be enhanced by resistance of tumor cells to the inhibitory effects of TGF-beta1 on normal B-cell proliferation and Ig secretion.  相似文献   
83.
ObjectivesThis study aims to provide insight into (i) how the combination of paid work and family care is longitudinally associated with gender-related differences in depressive symptoms and (ii) the role of work characteristics in this association.MethodsData were derived from STREAM, a Dutch prospective cohort study of older workers aged 45–64 years. Respondents were included if they were employed in at least one measurement between 2015 and 2017 (N=12 447). Mixed-models were applied to disentangle between-person (BP) and within-person (WP) effects of family caregiving on depressive symptoms. Analyses were stratified by gender. Work characteristics (social support, autonomy, emotional and mental workload) were separately added to the multivariable models.ResultsFor older employees, family caregiving was positively associated with depressive symptoms between and within persons for both women [BP B=0.80, 95% confidence interval (CI) 0.52–1.08; WP B=0.32, 95% CI 0.08–0.56] and men (BP B=0.75, 95% CI 0.45–1.05; WP B=0.25, 95% CI 0.01–0.48). Social support at work reduced the adverse effect of family care on depressive symptoms for women (BP) and men (BP and WP). Emotional workload partly explained the effect of family care for both women and men (BP).ConclusionsThe longitudinal association between family care and mental health was similar for male and female employees. Resources at work (ie, social support) could protect caregiving employees against depressive symptoms. More research is needed regarding the relative impact of the care context compared to the work context of working family caregivers.  相似文献   
84.
To investigate the incorporation of oral rhesus-human reassortant rotavirus tetravalent (RRV-TV) vaccine into a routine immunization programme, RRV-TV or oral placebo was coadministered with a pentavalent diphtheria-tetanus-whole-cell pertussis-Haemophilus influenzae b (Hib)-inactivated polio vaccine and hepatitis B vaccine following a 3-4-5-mo schedule in a double-blind trial involving 249 infants. Seroconversion rates after 3 doses of rotavirus vaccine were 80% for rotavirus immunoglobulin A (IgA) and 93% for RRV neutralizing antibodies. Rotavirus vaccine did not interfere with the immune responses to diphtheria, tetanus, pertussis, Hib, poliovirus 1, 2 and 3, or hepatitis B. Following the first, second and third doses of vaccine, fever >38 degrees C on the day of vaccination was seen in 31%, 24% and 24%, respectively, with no difference between RRV-TV- and placebo-vaccinated children. This fever was presumably due to the whole-cell pertussis vaccine. Those vaccinees who received concomitant RRV-TV vaccine had another peak of fever around d 4 after the first dose, when 25% of them had fever >38 degrees C and 3% >39 degrees C. It is concluded that RRV-TV rotavirus vaccine can be given concurrently with other childhood immunizations following a 3-4-5-mo vaccination schedule. However, febrile reactions to RRV-TV rotavirus vaccine are common when the first dose is given at the age of 3 mo.  相似文献   
85.
Dewald  GW; Pierre  RV; Phyliky  RL 《Blood》1982,59(1):100-105
Structural abnormalities of the X chromosome are rarely found in neoplastic disorders. We describe three patients with a history of idiopathic acquired sideroblastic anemia (IASA); each one had an abnormal clone of cells in the bone marrow, characterized by a structurally abnormal X chromosome. In two of these patients, the predominant karyotype was 47,X,2idic(X)(q13); in the other patient, it was 46,X,t(X;11)(q13;p15). Inasmuch as all three of these cases involved chromosome band Xq13, as did two previously published cases, we suggest that band Xq13 may be more prone to structural rearrangement than other X chromosome bands in hematologic disorders. The common Xq13 chromosome breakpoint and clinical presentation (IASA) among these three patients and the occurrence of an X-linked type of sideroblastic anemia may suggest that an association exists between X chromosome abnormalities and IASA. Perhaps alteration of a gene or chromosome structure in or near band Xq13 predisposes to development of IASA. The fact that two of these patients had preleukemia and the third had overt acute leukemia may imply that patients with IASA and X chromosome abnormalities have a poor prognosis. Cases of IASA without associated X chromosome abnormalities are known; thus, if an association between IASA and an abnormal X chromosome does exist, most likely it involves only some patients with IASA.  相似文献   
86.
Intestinal permeability can be assessed non-invasively using the lactulose-rhamnose (L-R) test, which is a reliable measure of small intestinal integrity. AIMS: To determine risk factors for abnormal intestinal permeability in kwashiorkor, and to measure changes in L-R ratios with inpatient rehabilitation. DESIGN: A case-control study of 149 kwashiorkor cases and 45 hospital controls. The L-R test was adapted to study kwashiorkor in Malawi, with testing at weekly intervals during nutritional rehabilitation. Urine sugars were measured by thin layer chromatography in London. RESULTS: The initial geometric mean L-R ratios (x100) (with 95% confidence interval) in kwashiorkor were 17.3 (15.0 to 19.8) compared with 7.0 (5.6 to 8.7) for controls. Normal ratios are < 5, so the high ratios in controls indicate tropical enteropathy syndrome. Abnormal permeability in kwashiorkor was associated with death, oliguria, sepsis, diarrhoea, wasting and young age. Diarrhoea and death were associated with both decreased L-rhamnose absorption (diminished absorptive surface area) and increased lactulose permeation (impaired barrier function) whereas nutritional wasting affected only L-rhamnose absorption. Despite, clinical recovery, mean L-R ratios improved little on treatment, with mean weekly ratios of 16.3 (14.0 to 19.0), 13.3 (11.1 to 15.9) and 14.4 (11.0 to 18.8). CONCLUSION: Abnormal intestinal permeability in kwashiorkor correlates with disease severity, and improves only slowly with nutritional rehabilitation.  相似文献   
87.
88.
New N-methylpiperazino-substituted quinazolines 8 and 9, phthalazine 13, and quinoline 19 have been synthesized. The receptor binding profiles (α1, 5-HT1A, 5-HT2A) of these compounds and their analogs (7–22) have been determined. It has been demonstrated that orientation of a local dipole moment of the heteroaromatic ring system affects both the α1 and 5-HT2A affinity of the investigated class of ligands. Distortion of the coplanar unfused heteroaromatic ring system results in a decreased 5-HT2A affinity. 4-(4-Methylpiperazino)-2-(2-thienyl)quinoline 18 is the most active and selective α1 ligand (Ki = 4.9 nM) with a much lower affinity for 5-HT1A (Ki = 3420 nM) and 5-HT2A (Ki = 211 nM) receptors.  相似文献   
89.
Gellan gum (GG)‐based hydrogels are advantageous in tissue engineering not only due to their ability to retain large quantities of water and provide a similar environment to that of natural extracellular matrix (ECM), but also because they can gelify in situ in seconds. Their mechanical properties can be fine‐tuned to mimic natural tissues such as the nucleus pulposus (NP). This study produced different formulations of GG hydrogels by mixing varying amounts of methacrylated (GG‐MA) and high‐acyl gellan gums (HA‐GG) for applications as acellular and cellular NP substitutes. The hydrogels were physicochemically characterized by dynamic mechanical analysis. Degradation and swelling abilities were assessed by soaking in a phosphate buffered saline solution for up to 170 h. Results showed that as HA‐GG content increased, the modulus of the hydrogels decreased. Moreover, increases in HA‐GG content induced greater weight loss in the GG‐MA/HA‐GG formulation compared to GG‐MA hydrogel. Potential cytotoxicity of the hydrogel was assessed by culturing rabbit NP cells up to 7 days. An MTS assay was performed by seeding rabbit NP cells onto the surface of 3D hydrogel disc formulations. Viability of rabbit NP cells encapsulated within the different hydrogel formulations was also evaluated by Calcein‐AM and ATP assays. Results showed that tunable GG‐MA/HA‐GG hydrogels were non‐cytotoxic and supported viability of rabbit NP cells. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
90.
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